Suction cleaner



2 Sheets-Sheet 1 Filed April '8, 1959 I INVENTOR Mauriee 0. Slab! Y ATTORNEY Oct. 21, 1941.

M. D. STAHL SUCTION CLEANER Filed April 8, 19

2 Sheets-Sheet 2 INVENTOR Maurice J0. Sla /z] S laiaawa ATTORNEY fledarrangement in which the dirt bag is mount- Patented a. 21, 1941 UNITED STATES.

PATENT OFFICE to The Hoover CompslmN a corporation of Ohio rth Canton. Ohio,

Application April s, 1939, no.- 266,721

8Clalms.

This invention relates to improvements in suction cleaners and more particularly to animproved form of muiiier for suction cleaners serving to reduce the noise due to the rush of air through the suction system. i

One practical method of reducing so-called air-flow noises is to provide a muiller extending beyond the outlet from the fan chamber and consisting of a tubular member lined with a suitable absorbing material. However, there are certain practical limitations in the use of muffiers, particularly when adapted to a cleaner having a pivotally mounted handle supporting the outerend of a dirt bag. In such an arrangement, the mufller becomes adefinite obstruction to the free movement of the bag as it swings with the handleunless it be made sufficiently flexible to bend with the bag and then it is very likely to kink, thus closing off the discharge passage entirely.

Therefore, the object of the present invention is to provide an improved mumer arrangement whereby the effective area of sound-absorbin surface is obtained without unduly extending-its length into the dirt bag. Briefly, this result is obtainedby including a portion of the muiiler within the exhaust passage leading from the fan chamber and connecting it with the external portion through an intermediate flexible section, so that the muffler becomes an, articulated unit. And aside from the advantage of decreased length of mutlier throughout its external portion, there is the further novel feature of treating the exhaust passage for noise-reduction for it is in 35 tending rearwardly through the air pe from this region that a considerable part of the noise is created, due to the turbulence set up by the sudden change of velocity of the air leaving the fan chamber.

A preferred embodiment of the invention will now be described in connection with the accomnd sli htly Oblique, t

panying drawings, in which:

Figure 1 is a general view in side elevation of a typical suction cleaner with portions broken away to show the suction system and the articulated muflier-arrangement;

Figure 2 is a v'iew simiiar to Figure 1 showing the dirt bag and muffler assembly removed from the cleaner; me 3 is a top plan view of the rearend portion of the cleaner with portions broken away to showthe muiiier arrangement;

Figure 4' is a view rearmost section ofthe cleaner showing a modied outwardly, beyond the flexible section of the detachable connection at in side elevation of the I erai'form of a ring which mumer rather than forwardly thereof as shown in Figure 1.

The auction cleaner herein disclosed and to which the improved articulated muiller is par- 5 ticuiarly adapted, is of the standard design wherein the cleaner body is supported upon wheels to be maneuvered over thecarpet surface by means of a handle having pivotal connection with the cleaner body.

The cleaner comprises generally, a casing I supported upon pairs of. front and rear wheels 2, 2 and including a nozzle portion 3 extending across its forward end. A fan chamber 4, located centrally or the casing. I, houses a fan i driven by a motor concealed beneath the removable dome-like cover supported upon the easing l. The handle I is provided at its lower end with an inverted U-shaped bail 1a which straddles the'motor cover 6 and has pivotal connection with the cleaner casing." The handle is free to swing forwardly and rearwardly was the cleaner 1 is maneuvered over the carpet surface with the customary reciprocating motion. I

Referring now in greater detail to the suction-creating system, the nozzle portion 3 has the form of a chamber with adownwardly opening suction mouth and normally spaced in close proximity to the carpet surface. An air passage extends rearwardly from the nomle chamber and communicates with the fan chamber ,through an annular inlet opening or eye In in its bottom wall. By preference, a rotary carpetcontacting member 8 is mounted in the nozzle chamber and is driven by means of a belt 0 exthe nozzle and having driving connection with the fan 5 through a pulley ll formed at the lower end of an extension In of the fan hub.

Extending rearwardly from the fan chamber the longitudinal center line of the cleaner body i s the exhaust e I I through which the dirtladen air is discharged into a dirt bag I! of the usual porous-fabric construction having its lower end mounted for the discharge outlet ber and its outer end sus handle I. The extreme rear II is preferably from the fan c pended from the I endof the exhaust e flanged atlla toprovideaseattowhlchthedirt' has supporting ring it is removably clamped. In the present disclosure. this bag ring it is incorporated in the muffler assembly, but consideredmerely as an attaching fitting for the mouth portionof the bag [2, it has the genflts flush against the flanged outlet connection Ha at the rear end of the cleaner body and is provided on opposite sides with hook-shaped lugs I 30, Ha which flt over corresponding bolts H, ll projecting rearwardly from the face of the flanged outlet connection and having ornamental heads a, Ila, as shown in Figure 3. The mouth of the bag I2 is secured around the ring ii in any suitable manner as for instance, by means of a metal clamping ring I 5 inserted in the mouth of the bag and seating on a shoulder on the outer face of the ring.

Referring again to the discharge outlet passage H, the same leads rearwardly from the fan chamber in a direction slightly oblique to the longitudinal axis of the cleaner body, so that the dust-laden air leaves the fan chamber in a path generally tangential to the periphery of the fan. Immediately beyond the port deflning the entrance to the exhaust passage, the latter undergoes an abrupt increase in its transverse'and vertical direction as indicated by the rearwardly facing shoulders llb formed just beyond the port. Moreover, the exhaust passage H is rectangular in cross section, somewhat elongated horizontally and having a slight divergencetoward its outer end as. shown in Figure 3.

Now, the increase in the transverse dimensions of the exhaust passage ll beyond that otherwise necessary for handling the air discharged from the fan chamber is a matter of approximately an inch in each direction, this enlargement of the exhaust passage making it possible to accommodate a portion of the muilier, preferably forming a partof a detachable bag and muiiier assembly now to be described in detail.

Generally, the muii'ier has the form of a tubular member consisting of an outer shell and an inner lining composed of a relatively thick layer I! of any suitable sound-absorbing material such as sponge rubber, cellulose padding or like material.

In the muiiier arrangement disclosed, a sectional construction has been adopted so as to introduce a certain degree of flexibility intermediate its end portions and for the reasons already mentioned. Thus, as clearly shown in Figure 1, the muilier proper is made up of an internal section It extending forwardly from the supporting ring ll andinto the enlargedexhaustpassage ll. Jmt beyond the internal section is a bellows-like section ll extending a short distance beyond the supporting ring II and in a direction outwardly therefrom, and finally, there is an external section ll which projects into the lower end portion of the dirt bag I: and is inclined slightly in an upward direction following general]! the inclination of the bag itself.

Refen'ingnowtosomeofthedetaikofconstruction of the muiiier, the internal section II which flts into the enlarged exhaust passage ll, includestheoutermetsllicshell Hamming its portion of the sound-absorbing member and suitably fastened to the supporting ring II. In addition to the outer metallic shell "a, the internalsection liispreferabiyprovidedwitha perforated sheetmetalinnerlinerllasapsotection tothesoft sound-absorbing material against thesevereabrasiveeifectofthedirtparticlesand other objects discharged from the fan chamber. Infact,alongonesideoftheexhmstm.ls showninl'igure3,itmaybedcsirabletoomit the sound-absorbing lining entirely, because of thelikeiihoodoi'pinsandotherpointedobiccts behigdrivenagainstthesm'facewithnichforce as to penetrate the perforations and become flrmly imbedded in the sound-absorbing material. Howeventhe treatment of the sound-absorbing surface throughout the exhaust passage is a matter of choice, although it can be stated that the use of a perforated sheet metal liner does not reduce the effectiveness of the sound-absorbing layer materially.

In any case, the internal section it extends through the supporting ring it where it Joins the short angular flexible section H which preferably consists of a bellows constructed of a suitable flexible sheet material, so that it can flex readily through a limited angle in the movement of the outer section II.

The outermost section I is essentially a continuation of the intermediate flexible section i1 and includes the greater length of the soundabsorbing material, but preferably omits the perforated metal lining, it being assumed that the material is capable of withstanding the abrasive effect of the dirt particles throughout this portion of the muiller. In any case, the outer section isof rigid construction by reason of a metal shell Ila which houses and supports the soundabsorbing material. And flnally, it is preferred to increase slightly the diameter of the air passage throughout the flexible and outer mumer sections I1 and II so as to reduce any tendency for the creation of a back-pressure by reason of any restrictiveeflect on the muiiier.

Owing to the weight of the extended outer muffler section It, it is further desirable to support it upon the ring II by mans-of a suitable hinged connection as at 2|, Just above the flexible section l1. The hinge-may be of any simple construction. as a projecting toward each other from the upper pin, joining the ends of short arms mu'iller exposed to view and also to a greater degree of wear, it is preferred to enclose the flexible section of the sound-absorbing material within a short bellows member 21 formed of some suitable sheet material, into which the sound-absorbing material is pressed or molded, but otherwise maintaining its continuity throughout the full length of the muffler. In other respects the bag and mufller are assembled and removably attached to the outlet connection from the cleaner, in the same manner as hereinbefore described.

From the foregoing description, the advantages of the muffler arrangements hereinbefore mentioned will be readily appreciated. In the first place, the over-all length of the muiiier has not been sacrificed, although the eifect of decreased length has been attained by inserting a portion of its length into the body of the cleaner and throughout the exhaust passage which ordinarily is not treated for noise reduction. Another advantage is the practical application of a muliler to a cleaner of the type in which the handle swings relatively to the cleaner body and supports the outer end of the bag, thus introducing considerable flexing at the mouth portion of the bag and otherwise making it quite impractical to use a muiiler of any-considerable length.

And finally, with the mufller forming an integral part of the bag assembly, it is possible to make renewals and ,replacements quite easily, inasmuch as the mufiier is removable from the cleaner as a unit and hence readily accessible. In fact,. this arrangement lends itself to the use of a muffler unit capable of being assembled as a part of the bag mounting, either for ready replacement in case of wear, or, in the event that it is deemed desirable to provide muiilers as optional equipment, to be attached or not as the user desires.

Thus, without limiting the invention to the specific features of construction herein disclosed, I claim:

1. In a suction cleaner, the combination with suction-creating means including a fan chamber having a passage leading to the exhaust outlet therefrom, of a muffler comprising a tubular member of sound-absorbing material and adapted to be attached at said exhaust outlet.

with a portion of its length extending into said passage to form a sound-reducing lining therefor.

2. In a suction cleaner, the combination with suction-creating means including a fan chamber having an exhaust passage of substantially increased transverse dimensions leading to a flanged outlet, of a mutlier comprising a relatively thick tubular body of sound-absorbing material adapted to be attached to said flanged outlet with a portion of its length extending throughout the length of said exhaust passage and forming a conduit for the air discharged from said fan chamber.

3. In a suction cleaner, the combination with suction-creating means including a fan chamber having an exhaust passage of substantially increased transverse dimension leading to a flanged outlet, of a mufiler comprising a tubular body of sound-absorbing material adapted to bev attached to said flanged outlet with a portion of its length conforming to the contour of said exhaust passage and adapted to extend into and throughout the length thereof to form a conduit for the air discharged from said fa'n chamber.

4. In a suction cleaner, the combination of suction-creating means including a fan chamber having an exhaust passage, and a muiiler comprising a tubular member of sound-absorbing material having one portion adapted to flt within and forming a sound-absorbing lining for said exhaust passage and another portion extending from and beyond said exhaust passage.

5. In a suction cleaner, the combination of suction-creating means including a fan chamber having an exhaust passage, a dirt bag adapted to be attached to the outlet from said exhaust passage, and a mufiler comprising a tubular member of sound-absorbing material divided into sections, one section being adapted to'flt within and form a lining for said exhaust passage and the other section projecting beyond the outlet from said exhaust passage and into said dirt bag.

6. In a suction cleaner, the combination of suction-creating means including a fan chamber having an exhaust passage, a dirt bag adapted to be attached to the outlet from said exhaust passage, and a muffler comprising a tubular member with walls of sound-absorbing material having a portion extending throughout the length of said exhaust passage and a portion projecting beyond said outlet and into said dirt bag, and means for attaching said mufller at said outlet.

7. In a suction cleaner, the combination of suction-creating means including a fan chamber having an exhaust passage and a flanged outlet connection, and a mufiler comprising a tubular member having a lining of sound-absorbing material and divided into flexibility connected sections, one section being adapted to fit within said exhaust passage with the other section projecting from and beyond said outlet, and a fitting carried by said mufiier for detachably connecting the same to said outlet connection.

' 8. In a suction cleaner, the combination of suction-creating means including a fan chamber having an exhaust passage substantially enlarged diametrically and a flanged outlet connection, a dirt bag adapted for detachable connection at said outlet connection, and a muiiler comprising a pair of'flexibly connected sections consisting of substantially rigid tubular members lined with suitable sound-absorbing material, one of said sections being adapted to fit within the enlarged exhaust passage to form a soundabsorbing lining therefor and the other section projecting beyond said outlet connection and into said dirt bag, and an attaching fitting intermediate the flexibly connected sections of said muiiier for connecting the same to said flanged outlet connection.

MAURICE D. STAHL. 

